1. Field of the Invention
The present invention relates to an apparatus for aligning electronic component chips, which is adapted to bring a plurality of electronic component chips, including passive components, active components and other electrical components, as well as not only completed chip-type electronic components but also semifinished electronic component chips, into a state aligned along a prescribed direction.
2. Description of the background Art
The assignee (applicant) has proposed a cassette storing a plurality of electronic component chips, which is adapted to provide the plurality of electronic component chips to an apparatus for supplying such electronic component chips, in Japanese Patent Application No. 62-96925 (corresponding to EP 0288277A2 and U.S. Ser. No. 184,112) etc.
The aforementioned cassette storing electronic component chips basically comprises a plurality of electronic component chips, a case which is provided with a storage space for storing the electronic component chips in its interior and an outlet communicating with the storage space for discharging the electronic component chips, and an openable closure for closing the outlet. A manufacturer of electronic component chips can directly use such a cassette storing electronic component chips as a packaging mode which is applicable to transportation of electronic component chips, while a user of electronic component chips can directly mount the cassette on a chip mounting apparatus for supplying a plurality of electronic component chips to a work site for performing a chip mounting step.
FIG. 6 is a sectional view showing a chip mounting step, which is carried out using a cassette 1 (shown in phantom lines) storing electronic component chips. The cassette 1 is directly mounted on an aligning apparatus 2 for electronic component chips, which serves as a hopper of a chip mounting apparatus. In more concrete terms, an outlet of the cassette 1 is directed to an opening 3 of the aligning apparatus 2 so that the cassette 1 is fixed to the aligning apparatus 2. Then a closure of the cassette 1 is so opened as to supply a plurality of electronic component chips 4, which have been stored in a storage space of the cassette 1, into the aligning apparatus 2 from the outlet. The electronic component chips 4, which are illustrated in a simplified manner in FIG. 6, are in the form of rectangular parallelepipes, for example.
The aligning apparatus 2 is generally inclined at an angle 5, which is selected to be about 45.degree., for example. The electronic component chips 4 supplied in the aligning apparatus 2 successively pass through a larger chamber 6 and a smaller chamber 7, to finally reach an aligning passage 8. The aligning passage 8, which is illustrated with a plurality of electronic component chips 4 in FIG. 6, is adapted to guide such a plurality of electronic component chips 4 to move in a state aligned along a prescribed direction. In order to attain such a function, the sectional dimensions of the aligning passage 8 are selected to be in certain relation to those of each electronic component chip 4.
The electronic component chips 4 are already aligned with each other when the same are introduced into an inlet 9 for the aligning passage 8, and are discharged from an outlet 10 while maintaining such an aligned state. Since the electronic component chips 4 discharged from the outlet 10 are aligned along a prescribed direction, it is possible to efficiently carry out the chip mounting step by handling the electronic component chips 4 while they continuously hold their aligned state.
The sectional area of the internal space provided in the aligning apparatus 2 is abruptly reduced at the boundary between the smaller chamber 7 and the aligning passage 8. Therefore, the electronic component chips 4 tend to jam in a portion of the smaller chamber 7 around the inlet 9 for the aligning passage 8. In order to prevent such jamming, a blowing passage 11 is provided in the vicinity of the inlet 9 for the aligning passage 8, to introduce compressed air from the exterior in an intermittent manner, for example. The compressed air thus introduced through the blowing passage 11 blows on the electronic component chips 4 jamming around the inlet 9 for the aligning passage 8, to agitate the same.
A number of such aligning apparatus 2 for electronic component chips are mounted on a chip mounting apparatus, for example, to be exchangeable with other types of aligners at need.
In general, such an aligning apparatus 2 is made of a metal. This is because relatively high wear resistance is required for the aligning apparatus 2 since wall surfaces defining the larger and smaller chambers 6 and 7 are struck and rubbed by the electronic component chips 4. Particularly higher wear resistance is required for the smaller chamber 7, whose wall surface is strongly struck by the electronic component chips 4, which are blown about by the compressed air from the blowing passage 11. On the other hand, it is necessary to eliminate static electricity, which is caused by collisions of the electronic component chips 4, through conductivity of the metal material, thereby attaining smooth movement of the electronic component chips 4.
While the aligning apparatus 2 for electronic component chips is generally made of a metal for the aforementioned reasons, the following problems are caused in relation to the metal material:
First, complicated or costly working steps such as cutting work or die-casting are required, in order to prepare the aligning apparatus 2 from a metal. Consequently, not only the cost is increased, not only for the aligning apparatus 2 itself but also for carrying out the chip mounting step, which employs a large number of such aligning apparatuses 2.
Further, the weight of the aligning apparatus 2 is increased because of the metal material, leading to increase the burden in handling such an aligning apparatus 2.